﻿/*
 * Copyright © 2002-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System.Reflection;
using System.Runtime.Serialization;

namespace Spring.Aop.Framework;

/// <summary>
/// <see cref="Spring.Aop.Framework.IAdvisorChainFactory"/> implementation
/// that caches advisor chains on a per-advised-method basis.
/// </summary>
/// <author>Rod Johnson</author>
/// <author>Aleksandar Seovic (.NET)</author>
[Serializable]
public sealed class HashtableCachingAdvisorChainFactory : IAdvisorChainFactory
{
    [NonSerialized] private Dictionary<MethodInfo, IList<object>> methodCache = new Dictionary<MethodInfo, IList<object>>();

    [OnDeserializing]
    private void OnDeserializing(StreamingContext c)
    {
        methodCache = new Dictionary<MethodInfo, IList<object>>();
    }

    /// <summary>
    /// Gets the list of <see cref="AopAlliance.Intercept.IInterceptor"/> and
    /// <see cref="Spring.Aop.Framework.InterceptorAndDynamicMethodMatcher"/>
    /// instances for the supplied <paramref name="proxy"/>.
    /// </summary>
    /// <param name="advised">The proxy configuration object.</param>
    /// <param name="proxy">The object proxy.</param>
    /// <param name="method">
    /// The method for which the interceptors are to be evaluated.
    /// </param>
    /// <param name="targetType">
    /// The <see cref="System.Type"/> of the target object.
    /// </param>
    /// <returns>
    /// The list of <see cref="AopAlliance.Intercept.IInterceptor"/> and
    /// <see cref="Spring.Aop.Framework.InterceptorAndDynamicMethodMatcher"/>
    /// instances for the supplied <paramref name="proxy"/>.
    /// </returns>
    public IList<object> GetInterceptors(IAdvised advised, object proxy, MethodInfo method, Type targetType)
    {
        if (!methodCache.TryGetValue(method, out var interceptors))
        {
            lock (methodCache)
            {
                if (!methodCache.TryGetValue(method, out interceptors))
                {
                    interceptors = AdvisorChainFactoryUtils.CalculateInterceptors(advised, proxy, method, targetType);
                    methodCache[method] = interceptors;
                }
            }
        }

        return interceptors;
    }

    /// <summary>
    /// Invoked when the first proxy is created.
    /// </summary>
    /// <param name="source">
    /// The relevant <see cref="Spring.Aop.Framework.AdvisedSupport"/> source.
    /// </param>
    public void Activated(AdvisedSupport source)
    {
    }

    /// <summary>
    /// Invoked when advice is changed after a proxy is created.
    /// </summary>
    /// <param name="source">
    /// The relevant <see cref="Spring.Aop.Framework.AdvisedSupport"/> source.
    /// </param>
    public void AdviceChanged(AdvisedSupport source)
    {
        methodCache.Clear();
    }

    /// <summary>
    /// Invoked when interfaces are changed after a proxy is created.
    /// </summary>
    /// <param name="source">
    /// The relevant <see cref="Spring.Aop.Framework.AdvisedSupport"/> source.
    /// </param>
    public void InterfacesChanged(AdvisedSupport source)
    {
    }
}
